开发者

How can I get codec information for a quicktime video in Objective C/Cocoa? (Without FFMPEG)

Hello and thanks for your time, I am creating a开发者_运维技巧n application that moves video files around to be processed by other applications. In the past, I have used mediainfo, and ffmpeg, in ruby to obtain codec information about each file. I would however like to transfer all of this into one beautiful cocoa app. I have searched and searched and still can't find a solution (without using ffmpeg) on how to do this. I am basically looking for the exact same info you get in the quicktime video inspector window (apple + i). Any help would be greatly appreciated, sample code, even more so. Thanks.


You can use Spotlight Queries (NSMetadataQuery), like the mdls command do :

> mdls ~/Music/iTunes/iTunes\ Media/iTunes\ U/WWDC\ 2011\ Session\ Videos\ -\ HD/1-01\ Apple\ Platforms\ Kickoff.m4v 
kMDItemAudioBitRate            = 103
kMDItemAudioChannelCount       = 2
kMDItemCodecs                  = (
    AAC,
    "H.264"
)
kMDItemContentCreationDate     = 2011-07-01 15:49:56 +0000
kMDItemContentModificationDate = 2011-07-01 16:13:39 +0000
kMDItemContentType             = "com.apple.m4v-video"
kMDItemContentTypeTree         = (
    "com.apple.m4v-video",
    "public.movie",
    "public.audiovisual-content",
    "public.data",
    "public.item",
    "public.content"
)
kMDItemDateAdded               = 2011-07-01 16:13:39 +0000
kMDItemDisplayName             = "1-01 Apple Platforms Kickoff.m4v"
kMDItemDurationSeconds         = 2787.754421087755
kMDItemFSContentChangeDate     = 2011-07-01 16:13:39 +0000
kMDItemFSCreationDate          = 2011-07-01 15:49:56 +0000
kMDItemFSCreatorCode           = "hook"
kMDItemFSFinderFlags           = 0
kMDItemFSHasCustomIcon         = 0
kMDItemFSInvisible             = 0
kMDItemFSIsExtensionHidden     = 0
kMDItemFSIsStationery          = 0
kMDItemFSLabel                 = 0
kMDItemFSName                  = "1-01 Apple Platforms Kickoff.m4v
kMDItemFSNodeCount             = 1147843844
kMDItemFSOwnerGroupID          = 20
kMDItemFSOwnerUserID           = 502
kMDItemFSSize                  = 1147843844
kMDItemFSTypeCode              = ""
kMDItemKind                    = "Video Media"
kMDItemLogicalSize             = 1147843844
kMDItemMediaTypes              = (
    Sound,
    Video
)
kMDItemPhysicalSize            = 1147846656
kMDItemPixelHeight             = 540
kMDItemPixelWidth              = 958
kMDItemProfileName             = "HD (1-1-1)"
kMDItemStreamable              = 0
kMDItemTotalBitRate            = 3287
kMDItemVideoBitRate            = 3184

Or you can check the AVFoundation framework.

Sample code:

 -(NSDictionary *) metadataForFileAtPath:(NSString *) path {
    NSURL *url = [[[NSURL alloc] initFileURLWithPath:path] autorelease];

    MDItemRef itemRef = MDItemCreateWithURL(NULL, (CFURLRef)url);
    NSArray *attributeNames = (NSArray *)MDItemCopyAttributeNames(itemRef);
    NSDictionary *attributes = (NSDictionary *) MDItemCopyAttributes(itemRef, (CFArrayRef) attributeNames);
    CFRelease(itemRef);

    // probably it is leaking memory (attributeNames and attributes), better check with Instruments

    return attributes;
}
0

上一篇:

下一篇:

精彩评论

暂无评论...
验证码 换一张
取 消

最新问答

问答排行榜